Field
One or more embodiments relate to a composite cathode active material, and a cathode and a lithium battery each including the composite cathode active material.
Description of the Related Technology
Lithium batteries with high voltage and high-energy density have a wide range of applications. In the field of electric vehicles such as hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles (PHEV), lithium batteries with high-energy density and high thermal stability that are operable at high temperatures with long lifetime and capable of charging or discharging a large amount of electricity are required.
To improve energy density of lithium batteries, a mixture of at least two cathode active materials with different particle diameters or a cathode active material with 2 or more peaks in particle size distribution may be used to improve filling density of the cathode active material. However, the use of at least two cathode active materials having different particle diameters may impede thermal stability of the lithium battery due to the smaller particle-diameter cathode active material that has a relatively low thermal stability and a large specific surface area cathode active material.
Therefore, there is a demand for a lithium battery with high energy density and high thermal stability.